JPH06269405A - Electronic endoscope - Google Patents

Abstract

PURPOSE:To provide a satisfactory image by eliminating problems caused by the protrusion or warp of an adhesive. CONSTITUTION:A light shielding film 7 is formed by photographing a black light shielding mask 11 into a transparent film 10, this light shielding film is sandwiched between two optical parts 5 and 6, and the shape of an optical image provided by an objective lens 3 is made quadrangular and incident on the photodetecting plane of a CCD 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic endoscope for viewing the inside of a subject by means of a CCD provided at the tip of a guiding tube.

[0002]

2. Description of the Related Art Conventionally, an endoscope shown in FIG. 4 is known as an electronic endoscope capable of seeing the inside of a subject.
The electronic endoscope 101 shown in this figure includes a guiding central tube portion 102 to be inserted into a body cavity of a subject, and an operating portion 103 provided on the proximal end side of the guiding central tube portion 102. When observing the inside of the body cavity of the examiner, the distal end side of the guiding central tube portion 102 is inserted into the body cavity from the subject's mouth or the like, and the operating portion 103
Is operated, whereby an image of the observation site is photographed by the imaging unit 104 arranged on the distal end side of the guiding hollow tube section 102, and this is operated via the signal line arranged in the guiding hollow tube section 102. After being guided to the CRT 1
It is projected on 07.

In this case, as shown in FIG. 5, the image pickup section 104 provided in the guiding hollow tube section 102 has the guiding hollow tube section 10 as shown in FIG.
An objective lens 110 provided at the tip of the second lens 2 and a CCD 112 for converting the optical image formed by the objective lens 110 into an image are provided, and the operation is performed via a signal line arranged in the guiding hollow tube section 102. When a drive signal is supplied from the unit 103, the optical image formed by the objective lens 110 is converted into an image by the CCD 112 and the image is transferred through the signal line arranged in the guiding tube unit 102.
After being led to 3, the data is transmitted to the apparatus main body 106 side through the universal cord 105 and displayed on the CRT 107.

[0004]

By the way, in the above-mentioned conventional electronic endoscope, the shape of the optical image focused by the objective lens 110 is circular, and the light receiving surface of the CCD 112 is quadrangular. The CCD 112 is arranged so that the light receiving surface is inscribed on the outer peripheral portion of the optical image, and the optical image is converted into an electric image (image).

However, the CCD 1
When the arrangement of 12 is performed, an unnecessary projection image is reflected by the inner wall of the lens barrel 113 or the like in the direction opposite to the light-receiving surface and is incident on the light-receiving surface, causing a harmful ghost in the image output from the CCD 112. There was an occasion.

Therefore, in order to eliminate such inconvenience,
As shown in FIG. 6, the light shield plate 1 made of a metal plate between the objective lens 110 and the CCD 112 and having the surface painted black.
A method has been developed in which 15 is arranged and the shape of the optical image obtained by the objective lens 110 is made into a quadrangle so as to be incident on the light receiving surface of the CCD 112, whereby the above-mentioned harmful ghost or the like does not occur.

However, when mounting the shading plate 115, the shading plate 115 is often sandwiched between the optical components 116 and 117 as shown in FIG. 7 for the purpose of stabilizing the position of the shading plate 115. Therefore, the adhesive 118 used when the light shielding plate 115 is brought into close contact with the optical components 116 and 117 protrudes and protrudes inside the light shielding plate 115, which changes the shape of the optical image incident on the light receiving surface of the CCD 112. Or the light shield 115 as shown in FIG.
The optical components 116 and 117 and the light shield plate 1 due to the warp of the light
There were times when it became impossible to make close contact with 15.

In view of the above circumstances, it is an object of the present invention to provide an electronic endoscope capable of obtaining a good image without the problems caused by the adhesive protruding or warping.

[0009]

To achieve the above object, the present invention provides an objective lens embedded at the tip of a guiding tube and a CCD for converting an optical image obtained by the objective lens into an electric signal. In an electronic endoscope having, it is configured by imprinting a light shielding mask on a transparent and flexible plate-shaped member,
It is characterized in that a light-shielding film sandwiched between two optical components arranged between the objective lens and the CCD is provided.

[0010]

In the above structure, the light-shielding plate formed by copying the light-shielding mask on the transparent and flexible plate-like member is sandwiched by the two optical components arranged between the objective lens and the CCD, thereby adhering. A good image can be obtained by eliminating problems caused by the agent's protrusion and warpage.

[0011]

1 is a side view of an image pickup portion showing an embodiment of an electronic endoscope according to the present invention. The image pickup section 1 of the electronic endoscope shown in this figure converts an optical image formed by the objective lens 3 provided at the distal end of a guiding tube section 2 constituting the electronic endoscope into an image. A CCD 4, an optical component 5 and 6 disposed between the CCD 4 and the objective lens 3, and a light-shielding film 7 fixed between the optical components 5 and 6. When a drive signal is supplied from the operation section via a signal line (not shown) arranged in the guiding tube section 2, the CCD 4 converts the optical image formed by the objective lens 3 into an image. Then, this is guided to the operation section through the signal line arranged in the guiding tube section 2 and then output to the outside.

In this case, the light-shielding film 7 is made as follows and is sandwiched between the optical components 5 and 6. First, as shown in FIG. 2, after a plurality of black light-shielding masks 11 are imprinted on one transparent film 10, scissors 1
This is divided into an appropriate size by 2 to form the light-shielding film 7, and the light-shielding film 7 is sandwiched by the two optical components 5 and 6 and fixed by an adhesive, and this is arranged in the lens barrel 9.

As described above, in this embodiment, the black light-shielding mask 11 is imprinted on the transparent film 10 to form the light-shielding film 7, which is sandwiched by the two optical components 5 and 6 and obtained by the objective lens 3. Since the optical image has a quadrangular shape and is incident on the light-receiving surface of the CCD 4, it is possible to obtain a good image without problems such as protrusion and warpage of the adhesive.

Further, in the above-mentioned embodiment, the black light-shielding mask 11 having a size corresponding to the size of the optical components 5 and 6 is imaged and separated by one transparent film 10 to separate the black light-shielding mask 11 and the light-shielding film. After making 7, the light-shielding film 7 and the optical parts 5 and 6 are positioned and fixed with an adhesive. However, as shown in FIG. 3, the size is smaller than the size of the optical parts 5 and 6. After the black light-shielding mask 21 is imprinted on the large transparent film 20, the transparent film 20 and the optical components 5 and 6 are positioned and fixed with an adhesive. The portion protruding from 6 may be cut off.

Even in this case, as in the above-described embodiment, a good image can be obtained without the problems caused by the protrusion and warpage of the adhesive. Further, in each of the above-described embodiments, the light-shielding masks 11 and 21 are imprinted on the transparent film 10 or the transparent film 20 to form the light-shielding film 7. However, the film is made of a transparent material and has flexibility. Any member may be used as long as it is a strip-shaped member.

[0016]

As described above, according to the present invention, it is possible to obtain a good image without the problems caused by the protrusion and warpage of the adhesive.

[Brief description of drawings]

FIG. 1 is a side view of an image pickup section showing an embodiment of an electronic endoscope according to the present invention.

FIG. 2 is a perspective view showing an example of a procedure for producing the light shielding film shown in FIG.

FIG. 3 is a perspective view showing an example of a procedure for producing a light-shielding film used in another embodiment of the electronic endoscope according to the present invention.

FIG. 4 is a perspective view showing an example of a conventionally known electronic endoscope.

5 is a side view showing a detailed configuration example of a photographing unit shown in FIG.

FIG. 6 is a perspective view showing an example of an optical system in which a light-shielding plate is used in a photographing unit in order to solve the conventional problems.

FIG. 7 is a side view for explaining a problem when a light shielding plate is used in the optical system.

FIG. 8 is a side view for explaining a problem when a light shielding plate is used in the optical system.

[Explanation of symbols]

 1 Image pickup part of electronic endoscope 2 Guide tube part 3 Objective lens 4 CCD 5, 6 Optical parts 7 Light-shielding film (light-shielding film) 9 Lens barrel 10 Transparent film 11 Black light-shielding mask 12 Scissors

Claims (1)

[Claims] 1. An electronic endoscope having an objective lens embedded at the tip of a guiding tube and a CCD for converting an optical image obtained by the objective lens into an electric signal, wherein a transparent and flexible plate-like member shields light. A mask is imprinted and arranged between the objective lens and the CCD 2
An electronic endoscope having a light-shielding film sandwiched between two optical components.